Preparation of nitrogen-doped lignin-based porous carbon materials and their application in a supercapacitor

Developing an efficient and green electrode material is vital for energy storage. Herein, a kind of lignin-based porous carbon material with different pore size distribution and high electrochemical properties was prepared by using alkali lignin as a carbon precursor doped with heteroatoms. The effects of different temperature gradients and pore structure on the properties of porous carbon with lignin as precursor were studied. The prepared material has high specific surface area of 1168.4 m²/g, rich pore size distribution, which was conducive to electron transfer and storage, and high nitrogen doping also improved the electrochemical properties of the carbons. The prepared lignin-based carbon material has a considerable specific capacitance of 302 F/g and higher level of cycle stability. The study not only provided a potential strategy for the preparation of cost-effective heteroatom-doped materials from lignin, but also offered a new insight for lignin valorization.